Fiat-Chrysler's former human resources director has pleaded guilty to lying to a federal grand jury to cover up a conspiracy to pay off top UAW officials.

Michael Brown, 60, entered his guilty plea Friday.

Brown was Fiat-Chrysler’s senior negotiator during collective bargaining talks with UAW-Chrysler in 2011 and 2015.

According to Detroit U.S. Attorney Matthew Schneider’s office, “Brown identified that the purpose of the conspiracy was to 'grease the skids' on behalf of FCA in its relationship and negotiations with the UAW.”

The “large-scale” conspiracy involved large payoffs, as well as golfing trips and other perks, to senior UAW leaders involved in union negotiations.

“The real victims here are the hard working men and women of the UAW, and my office will continue to pursue, expose, and prosecute corporate executives and union officials who put their own personal greed ahead of their duties to do their jobs," Schneider said in a statement.

Seven people have been charged as part of the conspiracy so far. Including Brown, six have now pleaded guilty.

Federal prosecutors say Fiat Chrysler negotiators bribed UAW negotiators in order to get contract concessions and other benefits. So far, one former FCA official, Alphons Iacobelli, and one former UAW official, Virdell King, have pled guilty in the conspiracy. More indictments are expected.

Fiat Chrysler CEO Sergio Marchionne says he'll step down next year after leading the combined company since 2009.

Marchionne, 65, told media at the Detroit auto show that FCA will release a business plan through 2022 around June. The company will announce his successor sometime after that. Candidates include Mike Manley, who leads the company's Ram and Jeep brands, and Reid Bigland, who leads the Alfa Romeo and Maserati brands and U.S. sales.